Deviation under Clouds
We have had a string of good weather and a few students were trying to get a cross-country flight in before I headed off to the Worlds. We also had clouds which is a rarity for us, it is much easier to play connect the dots when you can see them. The advantage is it makes it much easier to find the sheerline. The sheerline is not a straight line of lift, it is a wondering path to follow through the sky. With clouds it is easier to see what is going on.
However, sometimes it is hard to want to follow that wondering path when you have a turnpoint you are trying to achieve. Clouds make it easier to deviate, however, you have to make sure it a committed deviation. Even if you look at the clouds and you go under the edge, that doesn’t mean that’s where the lift is. You need to pay attention to what side of the clouds are producing the lift. And if that means they are on the far side of the cloud from where you are then you need to make the deviation to get to the good part of the cloud.
Wind can make the deviation feel worse. Let’s say you are on the downwind side of the cloud you might have to pass the cloud to get the thermal that is reaching up to the upwind side. This can be intimidating because you are expecting a good climb then run out from under the edge of the cloud, especially if you had traveled the entire length of the cloud. Use your past experience to make the decisions, use what you know about the day and what has been working. Do not half-heartedly make the deviation. Go for it.
Only partially making the deviation will just result in a longer flight while missing all of the lift and spending more time in sink.
We have talked about before about deviating 30 degrees without being too concerned about it. However when you make the deviation make it really count. Make sure to continue to look at the cloud for signs of where the lift is growing. Many times I have had students just get near the edge of the cloud, give up and head to the next one.
When you are looking at connecting the clouds you want to spend the least amount of time in the blue. A little wondering under the clouds is good. Being at cloudbase actually makes this more difficult. Take a look at the darker base, tendrils sucking into the clouds, shelves, windward side, and most important is what the last clouds have been doing. How have the last clouds been working?
But again it is easy to read all of the textbooks and read this article. Applying it is key. As we approached a cloud, I asked my student what part of the next cloud we should be using as our target, he had a good answer of what to do. However, we were headed about 20 degrees off from where he said we should be going.
When you are making your flight with an instructor it seems really easy, and a lot of it is. But the instructor in the back is helping with some guidance. Nothing, in particular, just making sure you are applying the knowledge, like going to the correct side of the cloud.
Garret Willat holds a flight instructor rating with over 8000 hours in sailplanes. His parents have owned Sky Sailing Inc. since 1979. He started instructing the day after his 18th birthday. Since then, Garret has represented the US Junior team in 2003 and 2005. He graduated from Embry-Riddle with a bachelor's degree in Professional Aeronautics. Garret represented the US Open Class team in 2008 and 2010 and the Club Class team in 2014. Garret has won 3 US National Championships.
